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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?lFFNshj2xv5Xyv+kbduf44sLOEBpxQY8GkTER+3xHIQCbbrIxwjQl/xnwOsV?= =?us-ascii?Q?/20F6IRr+nC47KTjldrU+9VRatWNWqW4q17GTiStc4K0Wm5ewc/myAfJ/uYK?= =?us-ascii?Q?UQI90op1kEY3mYFEan9MOixhzMAd1pD0Mx0DH0lyhlwbEYGfsalqzBFInmdg?= =?us-ascii?Q?915Akx+7sVz847g6ssuUnNDwpyS26dYKoIscEMQskU1196vY+yEAdyVqvw9c?= =?us-ascii?Q?V/k/yQnTPh+NbBQ8ULr6XBfMpqCBh1J2VNy+lgG4Y7AzgIVnKWh5Ok0H406t?= =?us-ascii?Q?Eg7vkHGt60sVWesbew4cMLCb/4Ax5EVCQcmggpNBYtyQOBxd+Wc0o07NxtMa?= =?us-ascii?Q?7awRRqEk+Qv3KNYF6C0CHzIU5PpXiWcp7GyVeZAD7tM4t2rx/RKALeBAOBcT?= =?us-ascii?Q?nbwcHXwYbBCDP9Al6XbPQ8JPCw8KpUswCcp0vEKyk1iMpk3WSpdhU5JW7bTZ?= =?us-ascii?Q?e8Ofhiv563xceXMjY8jfk8YgQxy4Kws3ptjiJdhp49eQK3AwjtJq4nORTTIt?= =?us-ascii?Q?ot/qFeIKKVhqloZhPurgf9xOK30hKsvARH35C7K8yaex60j3NcP1Tk6wwt9j?= =?us-ascii?Q?9TYvhc9tLlKpCTjcsyrP8UpKbPl+HmDtu6FlID+JjS9x0kg1hpwhCqEe+z0S?= =?us-ascii?Q?RK/auLZAIYlub5NtCUGbs64rBLAs9lAM10GijsDDpBKTW6+gy3wv/srEBv8v?= =?us-ascii?Q?fPxQyCGUjs+p4id0MoMcrV3BJ54rfoCodQdn8f/wsmm69F/YiICtkGCiE8za?= =?us-ascii?Q?oteg2/3050GGQ1uZTsQ5yPOgJ7N5eeJ0wjkmpXL0ZtUSuLKqdHki636+Xwbk?= =?us-ascii?Q?LIFO0d91iOkHF+r7EyCvhD04rcGvTyoWNp7FX0fE2A3NfVBH0PVWJ8RD92Z4?= =?us-ascii?Q?/JUfxhizrp0j1K2C/+G1NyLcR1FvrJgpL4TEkYG2OCuK5kst/9x6yKTeEk+D?= =?us-ascii?Q?yLqVazkp4TrSH4pkaKJGTHKektHhOJMImhkqnvrbhGmmYh8hwsy/vMV6YaXl?= =?us-ascii?Q?kJNidPGJVC8WS0STRUZfj849nAk2JQemnOv14MwIEIu3mdeDtOq8WJABMr77?= =?us-ascii?Q?BjYkOasWAjf8c3ZbI+TQl6zpFYBMifHclMYYr8jhlyl8+jrqCj5j8PIfziZu?= =?us-ascii?Q?HB0Vobg2r7TzZaNDDO5f07I8G5/A5/X3BsRLMaDLq0+3pIDMttBWZgXoZHXH?= =?us-ascii?Q?jrmakEERE9FX7O6YgEmkiBUickjMKdqhIh3lWGSsiCDYm8S8L8YscFfNilsG?= =?us-ascii?Q?qbZJ4ubn5qgc09jnCaFkaER1dcItF9Snfre2etR4+Eg2awkVWK2M+rittnsn?= =?us-ascii?Q?3CPtP5OT+dONIDaGbKm9LuFvHLhLpALMFEl0o9pBT99HTrkQRpE2DAf6p+U1?= =?us-ascii?Q?bBPKudoLnKOzz3HBZQDsw1IJ1pu8yTCSJ7ukAkAiK33KngBR/kunq+t+ZYcc?= =?us-ascii?Q?k5w0kyV6B9gPDs78L8CaBSURVbe6PlQtopDYP7xnf/1ieUEufxAOas/faGd6?= =?us-ascii?Q?iYYlT608sSHuImCf8tPKSiZdXefe60Bv5JXuD5fCKQ7GUXF5JTWewZlWk/YS?= =?us-ascii?Q?W9vg5QGU6UJM7t+Vr072OX5lUCv9rvLbSulDag/WLcSWG37wKX/Xm4m5pBvj?= =?us-ascii?Q?oFFPH1+ggk0d/q2dTYKuR7lSbcqmCG/lZdAqHrX1uDBwGubRA3/R3eG3DIsq?= =?us-ascii?Q?oLkmQ3JMiHxsiK766ESE9XuDBFQKv/yLeWqmwQ3f3HvqpBs/6LGj0Z5PrZKN?= =?us-ascii?Q?BvmTUbD+qA=3D=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: e9d5e255-9407-4a61-eba1-08df17f5556c X-MS-Exchange-CrossTenant-AuthSource: IA0PR12MB8374.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 21 Sep 2026 15:30:57.8620 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: mNbJNNLYzeR6PYksvfdTUD0YYGqIMznXMoAMXu47ObHHmKIxhXrWYx0plPO/aqXi X-MS-Exchange-Transport-CrossTenantHeadersStamped: PH9PR12MB995114 On 21 Sep 2026, at 1:42, Lance Yang wrote: > From: Lance Yang > > Handling the huge/shared zeropage correctly in vmf_insert_pfn_pmd() and > vmf_insert_pfn_prot() is more involved. We would need to check whether the > VMA allows it and keep the mapping read-only, similar to the checks in > vm_mixed_ok(). > > No in-tree user needs that support, so reject these mappings with > VM_FAULT_SIGBUS rather than complicate the code for now. > > Link: https://lore.kernel.org/all/20260917121010.60966-1-lance.yang@linux.dev/ > Suggested-by: Kiryl Shutsemau (Meta) > Suggested-by: David Hildenbrand (Arm) > Reviewed-by: Kiryl Shutsemau (Meta) > Signed-off-by: Lance Yang > --- > v1 -> v2: > - Reject the shared zeropage in vmf_insert_pfn_prot() (per Kiryl) - thanks! > - Explain the VMA validation and read-only requirements (per David) - thanks! > - Pick up Kiryl's Reviewed-by tag. > - https://lore.kernel.org/all/20260917121010.60966-1-lance.yang@linux.dev/ > > mm/huge_memory.c | 3 +++ > mm/memory.c | 3 +++ > 2 files changed, 6 insertions(+) > Makes sense to me. Acked-by: Zi Yan Best Regards, Yan, Zi